The invention relates to a cartridge for flowable media, comprising an envelope of a flexible material delimiting a volume, wherein the envelope can be provided at one end with a plunger-type pressing element and at the other end with an outlet element.
Cartridges for flowable media are known per se. They are containers for storing, transporting, and dispensing flowable media. Primarily, paste-like medias such as silicone rubber etc. are concerned, which are, for example, used in the construction industry. However, it is also known to fill adhesives, grease or other media into cartridges.
Different types of cartridges are known. In one type a sleeve or envelope delimiting a volume is provided in the form of a stable housing-like element which, in general, is provided at one end with a dispensing area and at the other end with an opening for a piston-like pressing element. The dispensing area comprises conventionally a dispensing opening, whereby it is known to close off the opening is by an element that is a unitary part of the envelope. When needed, this closing element is opened by cutting it open so that the dispensing opening results. In the area of the dispensing opening a socket provided with an inner or outer thread can be provided onto which a dispensing nozzle is placed. Such cartridges are primarily made of plastic so that with respect to their manufacture and disposal many expenditures are incurred.
The containers are primarily disposable containers because they cannot be completely emptied and they cannot be universally employed. Since the most favorable plastic is always selected for manufacturing the cartridges, they are not universally employable for all materials, but for different media different types of cartridges must be produced. A further problem is the incomplete and unsatisfactory emptying of the cartridges. Furthermore, it is easily possible that the operator becomes contaminated with the media. Finally, the produced empty cartridges are already of a size during transport to the filling station as they are after filling, i.e., they require a large transporting volume.
Stiff, tubular cartridges with a pressing area at one end and with a piston-shaped pressing element at the other end are emptied with a dispensing device into which the tubular element is clamped and with which the pressing element is moved by way of a pressure piston.
It is known to use, instead of the cylindrical containers, a hose container for the media to be dispensed. Such hose containers are comprised substantially of a foil hose which is closed off at both ends. It is known to close off the ends by so-called metal clips. The use of such hose containers is suggested primarily to avoid the disposal of a plurality of emptied cylindrical containers. The manufacture of hose containers is simpler and so is their disposal. Since the hose containers are not shape-stable, they are inserted into shape-stable cylindrical sleeves for dispensing the media contained therein whereby the sleeve has at one end a closure with a dispensing opening, for example, for arranging thereat a nozzle tip. At the other end of the cylindrical outer sleeve pressure can be applied onto the hose container. For dispensing the material contained in the hose container, the container must be opened, which in practice is achieved by destroying the hose container sleeve by slitting, puncturing etc. After emptying, the hose containers are removed from the cylindrical sleeves so that only a small, substantially empty hose container must be disposed of. Even though this is advantageous in comparison to cylindrical plastic cartridges, such hose containers have the disadvantage that they can only be used up to a certain filling volume, and it is especially disadvantageous that the dispensing device can be contaminated with the contained material. Also, the operator is usually also coming into contact with the medium. Often, a complete plugging of the dispensing means results so that, in practice, they must be disposed of also. Accordingly, the desired advantages are eliminated and the environmental impact caused by the disposal of the hose containers, on the one hand, and of the dispensing devices, on the other hand, is considerably increased. These disadvantages are even further complicated by the contamination of the operator, at the latest during removal of the hose container from the dispensing devices.
Hose containers are not shape-stable so that for dispensing of the media contained therein they must be inserted into a shape-stable cylindrical sleeve having at one end a closure with a dispensing opening, for example, for arranging thereat a nozzle tip. At the other end of the cylindrical outer sleeve pressure can be exerted on the hose container.
All of the cartridges of the aforementioned kind therefore have in common that their disposal is difficult and results in high disposal costs. Furthermore, the known cartridges cannot be universally employed, are inflexible with regard to their volume, and have disadvantages with respect to their uncontrollable handling.
Dispensing devices for cartridges of the aforementioned kind are known per se. A cylindrical receiving element, that is tubular or part-cylindrical, depending on the type of cartridge, has a dispensing area and a pressure generating device. The latter can be, for example, a pressure piston with which, by moving a lever, vacuum or an increased pressure within the cylindrical receiving element can be produced.
A prior art device has a pump piston which produces vacuum at the dispensing end of the cartridge, i.e., at the dispensing area of the cylindrical receiving member, and the flowable material thus is sucked out of the cartridge after opening.
However, it was found that such dispensing devices do not guarantee a complete emptying of the cartridges and, furthermore, do not ensure a defined behavior of the cartridge even within the tubular or cylindrical receiving member. A defined behavior is, for example, required for newer cartridges in order to ensure, on the one hand, a defined emptying of the remaining material and on the other hand a controlled folding of the cartridge material in order to make the empty cartridge to be disposed of as small as possible.
It is therefore an object of the present invention to provide a cartridge which is economical with regard to its manufacture and its filling, which is comprised of only a small amount of plastic and which only causes a minimal environmental impact upon disposal. Furthermore, an application as universally as possible should be provided, emptying as much as possible should be ensured, and a small transport volume should be provided.
Furthermore, the present invention provides a cartridge system which, in addition to a novel cartridge, also comprises a dispensing device and a pressure piston. With this complete cartridge system all economical and technical advantages of the new inventive cartridge can be optimally used and an optimal economic application is realized.